Naphthylamine carboxylic acid derivatives and process of making same



Patented Sept. 15, 1931 was? PATENT; OFFICE LEoroLn LASKHAAND OS ALPLLH ALLER, or onrENBAcmoN-rH -mAIN, GERMANY, As.- sronons T GENERAL ANILINE wonxs, INC", on NEW YORK, n. Y., A oonronn' 'rron I OF DELAWARE NAPHTHYLAMIN ,onnnoxirtio a (211 ,nEnIvA'rIvEs AND rnoonss or MAxiNosAME No Drawing Application filed I'March 3,1929, Serial no. 345,584, and in'Germany March; e, 1928.

Our present invention relates to naphthyl amino-hydroXy-phen'yl' K carboxylic ac id s, more particularly it're'lates to '1 (-2 '-naphth'ylamino) -4-l1ydroXy-phenyl carboxylic acids 5 of the following general formula:

x I ooon* wherein one X means hydrogen, h'alogemor an alkyl group and the other Xs mean hydrogen. These compounds are, obtainable by treating-an alkali salt of a: 1 (2-nap'hthylgeneral formula V ."a]1 {ali wherein the Xs have the aforesaid significanoe. with carbonic acid at elevated temperature and superatmospherio pressure. This course of reaction could notbe foreseen'since no carboxylic acids result by heating an alkali salt of a para-aminophenol with carbonic acid at superatmospheric pressure.

The carboxylicacids obtained byour process whereof those containing halogen or an alkyl group are new, may beemployedas intermediates for the production of' dyestuffs. In order to further illustrate our invention the following examples are given, the parts being by weight and all temperatures in centigrade degrees, but we wish it tobe understood that we are not limited to the particu- ,tioned therein:

Example 1.94l0 parts of 1(2-naphthylamino) l-liydoxy-benzene are dissolved in 267.2 parts of potassium hydroxide of 83% strength and 2000 parts of water. Then the water is distilled off in a vessel provided with a strong stirrer, finally in vacuo. The mass thus obtained is saturated when cool with car bonic acid while gradually increasing the pressure to 25 atmospheres. Then it is slow- 1y heated to 17 0 and maintained at this temamino) -l-hydroxyphenyl compoundof the andmi'xed with a dilute ferric chloride solu- When starting lar products nor reaction conditions men-.

* sagas,

.oHa

. erature for about 12 hours. The reaction mass 1s worked up by dissolving it in water,

filtering the solution and precipitating the 7 con It shows when dissolved in dilute alcohol tion a dark blue tint, whereas 1 (2 -naphthylamino) -l-hydroXy-benzene a n a l o g o u sly treated yields a dark red tint. i

from the sodium salt of 1-(2 naphthylamino) 4' hydroxy-benzene the process can be carried out in an analogous manner. I q

Example 2;249 parts of 1 (2' naphthylamino) 2 methyl 4 hydroxy-benzene are dissolved with 66 parts of potassium hydroxide of 83% strength in 750 parts of'water'.

-Then the solution is evaporated in vacuo untildry and the residue is treated with carbonic acid and worked up as des'cribedin Example 1. The'new l(2-naphthylamino) -2- m ethyllhydroxy-benzene' carboxylic acid thus obtained corresponds to the formula GOOH and represents, when recrystallized from toluene yellow leaflets melting at 213-214. Its dilute alcoholic solution becomes dark violet after the addition if ferriochloride.

" E a a iiple 3.'When 1 (2-naplithylamino -.3ahethyl 4-hydroXy-benzene is treated as described in Example 2, the new 1(2-naphthylprobably to the formula:

c' NH-QOH and crystallizes from toluene or xylene in the form of leaflets melting at 21 E215". Its alf a wherem one X means hydrogen and the other coholic solution shows a cherry-red color when mixed with ferric chloride. c I? We claimfl 1. A process which comprisestreating an alkali salt of a 1(2-naphthylamino)-4-hydroXy-phenyl compound of the general formula: i a

- co -Q wherein one X means hydrogen, halogen or w an alkyl group, the'other X hydrogein'with carbonic acid at a temperature of about 170 C. under superatmospheric pressure. r

2.A process which comprises treating an alkali salt of a 1(2-naphthylamino).-4c-hydroXy-phenyl compound of the general formula r V wherein one X means halogen oran alkyl group, the other X hydrogen, with carbonic acid at a temperature of'about 170 C. under NHQOH1 Y X 7X 1 wherein one X means halogen or analkylgroup, the-other Xs mean'hydrogen, which compounds are colorless crystallized substances, having a definite melting "point, soluble in alkalies, yielding areddish tobluish yielding a reddish to bluish color by mixing their'a-lcoholic solution with ferric chloride.

5. As new compounds the 1(2-naphthylamino) -4-hydroxy-methyl-phenyl carboxylic acids of the general-formula:

' coon methyl, which compounds are colorless crys- 'tallized substances, having a definite'melting point, soluble in alkalies, yielding a, reddish tobluish color by mixing their alcoholicsolution withferric chloride. I 1

6. As a new compound 1-(2-naphthyl amino-)= 4- hydroXy-2-methyl-phenyl-carboxylic acid of the-formula:

- 1 coon which compound forms whenrrecrystallized from toluene yellow leaflets melting at 213 to 214 0., and the dilute alcoholic solution of: which shows a dark violet coloration on the addition of ferric chloride. Y

- "7 As' a new compound 1- (2-naphthylamino) 4- hydroxy-3-methyl-phenyl-carboxylic acid of the formula:

which compound forms when recrystallized from toluene leaflets melting at 214 to 215 Cl and the dilute alcoholic solution of which shows a cherry-redcoloration on the addition 1 of'ferric chloride.

In testimony whereofwe aflix our signa- LEOPOLD 'LASKA.

tures' OSKAR HALLER. r

color by mixing theiralcoholic solution with i I ferric chloride.

4. As new compounds the 1(2 naphthyl- I amino) -4c-hydro'Xy-ph enyl carboxylic acids of the general formula:

oooH

wherein one X means a methyl group, the 

